base: Get rid of 'using' declaration of StringAppendF.

webkit/glue/webkit_glue.cc

Index: webkit/glue/webkit_glue.cc
diff --git a/webkit/glue/webkit_glue.cc b/webkit/glue/webkit_glue.cc
index c7a7d102c55367b2c4aace58062905d345ba4953..67b61bafff610dbe4a959c7436d34b6742df25b9 100644
--- a/webkit/glue/webkit_glue.cc
+++ b/webkit/glue/webkit_glue.cc
@@ -157,11 +157,11 @@ std::wstring DumpFrameScrollPosition(WebFrame* web_frame, bool recursive) {
 
   if (offset.width() > 0 || offset.height() > 0) {
     if (web_frame->parent()) {
-      StringAppendF(&result, L"frame '%ls' ", UTF16ToWide(
+      base::StringAppendF(&result, L"frame '%ls' ", UTF16ToWide(
           web_frame->name()).c_str());
     }
-    StringAppendF(&result, L"scrolled to %d,%d\n",
-                  offset.width(), offset.height());
+    base::StringAppendF(&result, L"scrolled to %d,%d\n",
+                        offset.width(), offset.height());
   }
 
   if (recursive) {